pack: initialise pack with base mods

These generally do not affect gameplay and the rest of the pack are
built upon this baseline.

mods/placeholder-api.pw.toml

@@ -0,0 +1,13 @@
+filename = 'placeholder-api-2.8.1+1.21.10.jar'
+name = 'Text Placeholder API'
+side = 'both'
+
+[download]
+hash = '92606640457931698f272e4e8866b5357767360e78a3eed8b3bd490e8a17bfeaefdc0bd444ac8ba4f51b7f9f1eb7f22337e034b409939db3601269d4b53ad22c'
+hash-format = 'sha512'
+mode = 'url'
+url = 'https://cdn.modrinth.com/data/eXts2L7r/versions/T5pDJV1K/placeholder-api-2.8.1%2B1.21.10.jar'
+
+[update.modrinth]
+mod-id = 'eXts2L7r'
+version = 'T5pDJV1K'